Natural extracts-meditated efficient and electrically responsive bioglues

Bioglues have great potential in the field of biomedical engineering concerning interfacial adhesion. Based on naturally extracted chitosan and benzoic acids, we developed low-viscosity bioglues capable of achieving an efficient and strong interfacial adhesion to wet skin tissues without any additional post-treatment. Owing to the synergy of topology, electrostatic interaction and self-hydrophobization, the adhesive strength could reach as high as 110 kPa when two pieces of fresh porcine skin were adhered together with the bioglues for one minute. Subsequently, we showed that the bioglue-regulated interfacial adhesion was essentially sensitive to external electrical fields with voltages less than 1 V, which might thus cause an electrically responsive adhesion. Likewise, we revealed that the phenol–quinone transition played a dominant role in inducing changes in interfacial adhesion strength modulated by the applied electric fields. By introducing a circuit model to mimic electric stimulation, we further recognized that an electric field of ∼2500 V/m was the threshold required for the electrically regulated phenol–quinone transition. Further, the bioglues were biocompatible, antibacterial and promoted wound healing, making them more suitable for applications in smart interfacial adhesion-related areas like biomedicine, flexible electronics and soft robotics.